The invention comprises a method for the non-invasive measurement of the properties of meat using a dual energy x-ray absorption scanner.
An important property of meat is meat yield Meat yield is a measure of the percentage of a block of meat that is fat and the percentage of the block of meat that is chemical lean. Together fat and chemical lean make up the block of meat. Other important properties of meat include weight of the meat, meat tenderness, the effective atomic number of the meat and the amount of contamination in the meat.
Dual energy x-ray absorption scanners produce output intensities of two different x-ray energies in different ways. An x-ray tube working at one voltage, for example 150 keV, will produce x-rays with energies from 150 keV down to 0 keV. To select two groups of x-ray energies from this distribution two detectors may be used where each detector is capable of measuring one of the two groups of x-ray energies required. These detectors may be string-like detectors housed above the conveyor belt in a line across the scanner surface. The two detectors may be placed one on top of the other, or alternatively side by side above the scanner surface. A second method for producing a dual energy output is to rapidly switch the x-ray source between two energy levels. In an x-ray absorption scanner of this form a single detector may be used to detect x-ray intensities at both x-ray energies.
It is He object of the present invention to provide an improved or at least alternative method for the non-invasive measurement of properties of meat.
In broad terms in one aspect the invention comprises method for assessing a property or properties of meat including the steps of scanning the meat using a dual energy x-ray absorption scanner to produce two images or arrays of values representative of the intensities of the x-rays at two energy levels, and processing the images or arrays of values to determine at least one property of the scanned meat.
Preferably the method includes the step of correcting the assessment for instrumental effects that may affect the assessment of the meat property or properties.
Preferably the method includes the step of assessing the mass centroid along at least one axis of the images or arrays of values and using this in the correction for instrumental effects.
Preferably the method includes the step of assessing the mass of the meat using the images or arrays of values and using this in the correction for instrumental effects.
Preferably the method includes processing only pixels or data points in the high x-ray intensity image or array that fall below a threshold value.
The images or arrays of values may also be stored for fixture retrieval and/or reprocessing.
The method for assessing a property or properties of meat may further include the steps of converting at least one red-green-blue image of the changes in atomic number into an intensity image and assessing the meat tenderness from the at least one intensity image.
The method for assessing a property or properties of meat according may further include the steps of individually extracting each component of a red-green-blue image of the changes in atomic number, processing each extracted component into an intensity image, analysing each image to determine changes in image intensity, producing a binary array for each component based on the changes in intensity, and assessing meat tenderness from the variations of the binary arrays.
In broad terms in a further aspect the invention includes an apparatus for assessing a property or properties of meat comprising a dual energy x-ray absorption scanner for scanning the meat and arranged to produce two images or arrays of values representative of the intensities of the x-rays at two energy levels, and an associated computer system arranged to process the images or arrays of values to determine at least one property of the scanned meat.
Preferably the computer system of the apparatus is arranged to correct the assessment for instrumental effects that may affect the assessment of the meat property or properties.
Preferably the computer system of the apparatus is arranged to assess the mass centroid along at least one axis of the images or arrays of values and use this in the correction for instrumental effects.
Preferably the computer system of the apparatus of the invention is arranged to assess the mass of the meat using the images or arrays of values and use this in the correction for instrumental effects.
Preferably the computer system of the apparatus of the invention is arranged to process only pixels or data points in the high x-ray intensity image or array that fall below a threshold value.
The apparatus of the invention may also be arranged to store the images or arrays of values for future retrieval and/or reprocessing.
The computer system of the apparatus of the invention may be further arranged to convert at least one red-green-blue image of the changes in atomic number into an intensity image and assess the meat tenderness from the at least one intensity image.
The computer system of the apparatus of the invention may be further arranged to individually extract each component of a red-green-blue image of the changes in atomic number, process each extracted component into an intensity image, analyse each image to determine changes in image intensity, produce a binary array for each component based on the changes in intensity, and assess meat tenderness from the variations of the binary arrays.